Zone controlled radiant heating system utilizing focused reflector

Abstract

A temperature control system (,) is provided for a plasma processing device (,). The plasma processing device (,) comprises a plasma generator (,) and a processing chamber (,) in communication with the plasma generator (,) such that plasma within the generator may pass into the chamber and react with the surface of a substrate (,) residing therein. The temperature control system (,) comprises (i) a radiant heater assembly (,) for heating the substrate (,), comprising a plurality of radiant heating elements (,) arranged in a plurality of zones (a-n), each zone comprising at least one heating element, and a focused reflector (,) for focusing radiant energy from the heating elements toward the substrate; (ii) a feedback mechanism (,) for providing a substrate temperature feedback signal (,); and (iii) a controller (,), including a P-I-D closed loop controller (,) and a lamp power controller (,). The P-I-D closed loop controller (,) receives a temperature setpoint signal and the temperature feedback signal and in response thereto independently adjusts a control variable sent to the lamp power controller. The power controller (,) then adjusts the power applied to the plurality of zones of radiant heating elements, independently of the control variable, based on temperature zone maps stored in processor memory. The power controller operates in at least a first ramp state and a second steady state, depending upon the magnitude of difference (&Dgr;) between the temperature setpoint signal and the temperature feedback signal.